An 8.4 Kb fragment of the NK-2 gene conferred the NK-2 pattern of gene expression on beta-galactosidase in transgenic lines of Drosophila. NK-2 patterns were not detected with smaller DNA fragments from the NK-2 gene. NK-2 protein was shown to be required, directly or indirectly, for continued maintenance of NK-2 gene expression. Further results on the three dimensional structure of the NK-2 homeodomain were obtained in collaboration with James Ferretti and his colleagues. The primary determinants of the nucleotide sequence of the NK-2 homeodomain binding site in DNA were shown to be interactions between Ile-47 of the homeodomain and A3 and A4 residues on the (+) strand of DNA and between Tyr-54 and T4, C5, and A6 in the (-) strand of DNA. Kinesin-73 cDNA was shown to encode a novel Drosophila kinesin heavy chain protein that contains an N-terminal motor domain and a long central region that lacks extensive coiled-coils. The amino acid sequence of the motor domain of kinesin-73 protein is most closely related to the motor domains of C. elegans unc-104 and mouse KIF1A. The C-terminal region of kinesin-73 protein contains a cytoskeleton associated protein Gly-rich domain, which is a putative microtubule binding site. Kinesin-73 mRNA is maternally expressed and widely distributed in the syncytial blastoderm embryo. However, later in Drosophila embryo development, expression of the kinesin-73 gene becomes restricted primarily to the CNS and PNS.